Journal of Biosciences最新文献

Plants respond to water scarcity by modifying transcription and metabolite accumulation; however, mechanisms leading to drought tolerance/sensitivity in chickpea (Cicer arietinum L.) are poorly understood. To understand the molecular basis of drought tolerance/sensitivity, the carbohydrate content and transcriptional changes in the genes of sugar, starch, abscisic acid (ABA), and gibberellic acid pathways were studied in a drought-tolerant genotype (ICC 8950) and a drought-sensitive genotype (ICC 3776). Droughts disrupted carbohydrate metabolism in ICC 3776, leading to decrease in starch content and increase in sugar content, including sucrose. In ICC 8950, under drought stress, the starch content remained unchanged but sugar levels increased slightly. The reduction in starch content in ICC 3776 resulted from increased degradation rather than decreased synthesis, whereas in ICC 8950, starch anabolism as well as catabolism genes were downregulated, leading to unchanged starch levels. The increase in sucrose content in ICC 3776 under drought stress resulted from lower degradation due to the downregulation of cell wall invertase. The expression of ABA catabolism genes under drought increased in ICC 3776 but decreased in ICC 8950, suggesting increased ABA content in ICC 3776 but not in ICC 8950. This study showed that drought causes a decrease in the starch content and an increase in the sucrose and ABA contents in the drought-sensitive genotype, whereas the drought-tolerant genotype maintains starch and sucrose levels coupled with lower ABA.

Glyphosate-based herbicides (GBHs) can be found in waterbodies and may affect aquatic populations, resulting in physiological and behavioral impairments. In Colombia, white cachama (Piaractus orinoquensis) are frequently found in areas subjected to glyphosate aerial fumigation. This study aims to investigate changes in c-Fos protein expression in P. orinoquensis telencephalic hemispheres after exposure to 0, 1, 5, and 10 mg/L glyphosate for 30, 60, and 90 min. For this purpose, 5 lm paraffin sections were obtained and used for c-Fos immunodetection. To define the effect of xenobiotics on c-Fos expression, nuclei were taken from the dorsal dorsal (Dd), dorsomedial (Dm), dorsal posterior (Dp), dorsolateral (Dl), ventral (Vv), dorsoventral (Vd), and ventrolateral (Vl) regions of P. orinoquensis telencephalic hemispheres. Except for Dd nuclei, other nuclei showed an initial increase in c-Fos+ cells, followed by a progressive decrease toward values similar to those observed in unexposed individuals. In Dd nuclei, the initial tendency was toward a reduced number of c-Fosexpressing cells, followed by an increase in unexposed values. As changes in the number of cells containing c-Fos can be related to changes in neuronal activity, GBH exposure may potentially affect the fish's behavioral and sensorial performance, resulting in a reduced survival probability in its natural environment.

The capability of neurons to regenerate after injury becomes poor in adulthood. Previous studies indicated that loss of either let-7 miRNA or components of insulin/insulin-like growth factor signaling (IIS) can overcome age-related decline in axon regeneration in Caenorhabditis elegans. In this study, we wanted to understand the relationship between these two pathways in axon regeneration. We found that the simultaneous removal of let-7 and the gene for insulin receptor daf-2 in parallel increased functional recovery involving posterior touch sensation following axotomy of posterior lateral microtubule (PLM) neurons in adulthood. Conversely, the loss of let-7 could bypass the regeneration block due to the loss of DAF-16, a transcriptional mediator of DAF-2. Similarly, the loss of daf-2 could bypass the requirement of LIN-41, a transcriptional co-factor of the let-7 pathway. Our analysis revealed that these two pathways independently control the targeting of the regenerating axon to the ventral nerve cord (VNC), which leads to functional recovery. The computational analysis of the gene expression data revealed that a large number of genes, their interacting modules, and hub genes under the let-7 and IIS pathways are exclusive in nature. Our study highlights a potential to promote neurite regeneration by harnessing the independent gene expression program involving the let-7 and IIS pathways.

Reproductive status influences metabolism and health across the lifespan in diverse ways, and mitochondrial function plays a critical role in mediating this relationship. Using the Caenorhabditis elegans germline ablation model, we investigated the impact of germline stem cell (GSC) loss on mitochondrial dynamics and respiratory function. Our results show that GSC loss reduces mitochondrial volume and respiratory function in young adulthood but preserves mitochondrial activity during aging and upon exposure to hypothermic stress, correlating with enhanced survival. We found that the transcription factor NHR-49/PPARα, but not DAF-16/ FOXO3A, was essential for preserving mitochondrial function and hypothermia resistance in these long-lived mutants. Together, these findings reveal the impact of germline signals on somatic mitochondrial health and underscore the intricate relationship between reproductive fitness and organismal health.

Diabetes involves complex metabolic dysregulation and necessitates approaches such as α-amylase inhibition to moderate postprandial glucose spikes and hyperglycemia. Thus, this study scrutinizes the α-amylase inhibitory potential of selected traditional rice varieties (Athur Kichili Samba, Poonkar, Karuppu Kavuni) as well as a modern variety (CO 43) in the cooked condition, using computational approaches alongside in vitro validation. The 156 metabolites obtained from gas chromatography-mass spectrometry analysis, docked with human pancreatic α-amylase (HPA), and based on the binding energies top-five-ranked metabolites were shortlisted (PubChem IDs: 91714169, 13821354, 167795, 2756016, and 3075922). In addition, molecular dynamics simulation was carried out for a timescale of 200 ns to assess protein-ligand complex stability, with parameters such as root mean square deviation, root mean square fluctuation, radius of gyration, solventaccessible surface area, H-bond, and interaction energy. Furthermore, molecular mechanics Poisson- Boltzmann surface area (MM/PBSA) and molecular mechanics generalized Born surface area (MM/GBSA) analyses were performed to validate the selected inhibitors. In vitro studies corroborated inhibitory effectiveness, with Athur Kichili Samba having the highest potency (IC50=4.48 mg/mL), followed by CO 43, Poonkar, and Karuppu Kavuni (IC50=5.12, 6.29, and 11.35 mg/mL). The consistent ranking of antidiabetic functionality observed across both computational and experimental approaches highlights the potential of these traditional rice varieties, suggesting additional clinical investigations to endorse their global consumption.

The Johanson-Blizzard syndrome (JBS) is a complex autosomal recessive disorder that manifests through a spectrum of symptoms, with deficiencies in the ubiquitin-protein ligase E3 component N-recognin 1 (UBR-1) at its genetic core. Despite its clinical significance, the molecular intricacies of UBR-1's role in JBS remain largely elusive, presenting a formidable challenge in devising targeted treatments. The nematode Caenorhabditis elegans, with its genetic tractability and conservation of fundamental biological mechanisms, emerges as an invaluable model for unravelling the molecular underpinnings of JBS. This review integrates the latest discoveries from C. elegans studies, shedding light on UBR-1's multiple functions: its regulatory impact on cellular pathways and, particularly, its crucial involvement in glutamate metabolism. By assessing the contributions of these studies to our understanding of JBS, this review highlights the potential significance of glutamate metabolic dysfunction in JBS pathogenesis.

Our knowledge of how and why various biological and ecological traits relate (scale) to body size has grown at a rapid pace. In this exploratory analysis, I aim to further advance our knowledge of biological scaling by arguing that individuality and selfhood increase along a size spectrum from tiny microbes to huge trees and whales, as driven by a gradient of decreasing mortality. According to a proposed size-self spectrum (SSS) model, tiny short-lived organisms are continuously engaged in relatively rapid, all-consuming, selfless reproduction, whereas large long-lived organisms have evolved relatively high levels of individuality and selfpreservation. Grades of individuality in organisms along the SSS are recognized by their levels of development of (a) protective boundaries between their inner and outer environments, (b) autonomy and identity preservation, and (c) self-awareness and regulation. Paradoxically, as increasingly large organisms have evolved increased independence from their external environments, they have also exerted greater per-capita impacts on them. With increasing body size, the prevailing direction of influence of an individual organism's internal versus external environments switches from inward in small 'exocentric' species to outward in large 'endocentric' species. Implications of the SSS model for understanding the nature and environmental impact of humans, who are relatively large organisms, as well as various other controversial biological, ecological, and philosophical issues are discussed.

Climate change is a significant global issue characterized by rising temperatures, altered weather patterns, and increased frequency of extreme weather events. It can have immediate and serious implications for global health, both directly and indirectly. The latest reports suggest that several climatic factors can alter health parameters, many of which could directly impact ocular health. This review discusses how aspects of climate changes that include increased frequencies of severe weather events, such as floods, heatwaves, extreme temperatures, rising carbon dioxide, and rising sea levels, may influence ocular health. Similarly, air and water pollution, food scarcity, disruption of healthcare delivery systems and medical supply chains, as well as an increase in zoonoses and food-, water-, and vector-borne diseases can affect multiple organs, including the eyes. Reports suggest that the repercussions of climate change and its consequences can have a more substantial effect on a specific subset of people, including elderly, low-income, physically disabled, and malnourished populations. This review aims to provide a perspective on the relationship between climate change and its impact on human ocular health, including epidemiological shifts in the occurrence of ocular problems. This review also discusses how climatic shifts cause ocular problems and emphasizes their effects on specific population groups.

Bemisia tabaci (Gennadius), one of the most destructive insect pests worldwide, damages plants and transmits numerous harmful virus species, including begomoviruses. One novel control approach that has been suggested is silencing the vacuolar H⁺-ATPase (V-ATPase), a vital enzyme found in the endomembranes and plasma membranes responsible for pH homeostasis. Engineered V-ATPase dsRNA can be delivered to B. tabaci through feeding (via transgenic plants as well as root and foliar delivery of naked or formulated dsRNA) and non-feeding (spraying dsRNAs and recombinant entomopathogens) methods. This review considers the potential use of V-ATPase RNAi in combination with cultural/mechanical practices, biorational insecticides/ natural compounds, natural enemies, and biotechnological control strategies. These approaches are promising for integrated whitefly management (IWM) programs, and can potentially reduce excessive use of chemical pesticides and the likelihood of pesticide resistance. Despite their specificity and high efficiency, emerging resistance and the effects on non-target organisms remain concerns. Also, RNAi of different subunits could lead to various outcomes, and V-ATPase silencing may show dissimilar effects against various whitefly biotypes. Here, some challenges have been addressed with various solutions, e.g., appropriate formulations for protecting, carrying, and spreading dsRNAs, along with the use of strong promoters to optimize the effective dosage of the administered dsRNA molecules.

Numerous scientific studies have established that the BCG vaccination reduces susceptibility to bacterial and viral infections, particularly those causing respiratory tract ailments. This effect is partly attributed to the crossreactivity of BCG antigens, which reinforces immunity and presents an important avenue for therapeutic interventions against bladder cancer, Buruli ulcer, and leprosy. Remarkably, individuals residing in tuberculosis (TB)-endemic regions who have received BCG vaccinations exhibit a significant reduction in the incidence of monkeypox virus (MPV) infections. This observation could be attributed to shared T-cell and B-cell epitopes between mycobacteria and MPV, raising the possibility of eliciting cross-reactive immune responses. Such cross-reactivity could account for the enhanced protection conferred by the BCG vaccination against MPV infections. To explore this possibility, we employed advanced immunoinformatics tools. Our analysis successfully identified common CD4 T-cell, CD8 T-cell, and B-cell epitopes shared between MPV and mycobacteria. Notably, the T-cell epitopes demonstrated high immunogenicity and substantial affinity, with promiscuous binding to multiple human leukocyte antigen (HLA) class I and class II alleles, indicating the potential for these epitopes to trigger robust immune responses. Indeed, the predicted outcomes encompassed the induction of Th1-cell and Th2-cell responses via the predicted epitopes. These findings carry profound implications. They imply that prior exposure to cross-reactive mycobacterial antigens during recent pandemics could have contributed to increased levels of protection against MPV infections in TB-endemic regions, in contrast to areas non-endemic for TB. The identified T-cell and B-cell epitopes may thus serve as promising candidates for developing vaccines to combat MPV and mitigate its spread.